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What extension cords must be used with portable electric tools on a construction site?
Three-wire grounded cords designed for hard usage.
- Two-wire cords, if used indoors
- Any household extension cord
- Three-wire cords made for hard usage ✔
Why: 1926.405(a)(2)(ii)(J) says extension cords used with portable electric tools must be three-wire and designed for hard or extra-hard usage.
Huh, didn't know that: The third wire provides the equipment grounding path for workers.
Why did the extension cord have three wires? It was well grounded.
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References
Answer: Three-wire cords made for hard usage. 1926.405(a)(2)(ii)(J) says extension cords used with portable electric tools must be three-wire and designed for hard or extra-hard usage.
- 29 CFR 1926.405(a)(2)(ii)(J) www.law.cornell.edu/cfr/text/29/1926.405
Extension cord sets used with portable electric tools and appliances shall be of three-wire type and shall be designed for hard or extra-hard usage.
Checked 2026-10-10.
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